Fish, contaminants and human health: quantifying and weighing benefits and risks

Guidance on risk-benefit assessment of foods

The EFSA Scientific Committee has updated its 2010 Guidance on risk-benefit assessment (RBA) of foods. The update addresses methodological developments and regulatory needs. While it retains the stepwise RBA approach, it provides additional methods for complex assessments, such as multiple chemical hazards and all relevant health effects impacting different population subgroups. The updated guidance includes approaches for systematic identification, prioritisation and selection of hazardous and beneficial food components. It also offers updates relevant to characterising adverse and beneficial effects, such as measures of effect size and dose-response modelling. The guidance expands options for characterising risks and benefits, incorporating variability, uncertainty, severity categorisation and ranking of different (beneficial or adverse) effects. The impact of different types of health effects is assessed qualitatively or quantitatively, depending on the problem formulation, scope of the RBA question and data availability. The integration of risks and benefits often involves value-based judgements and should ideally be performed with the risk-benefit manager. Metrics such as Disability-Adjusted Life Years (DALYs) and Quality-Adjusted Life Years (QALYs) can be used. Additional approaches are presented, such as probability of all relevant effects and/or effects of given severities and their integration using severity weight functions. The update includes practical guidance on reporting results, interpreting outcomes and communicating the outcome of an RBA, considering consumer perspectives and responses to advice.

Quantitative risk-benefit assessment of Portuguese fish and other seafood species consumption scenarios

Portugal has high fish/seafood consumption, which may have both risks and benefits. This study aims to quantify the net health impact of hypothetical scenarios of fish/seafood consumption in the Portuguese population using a risk-benefit assessment methodology. Consumption data from the National Food, Nutrition and Physical Activity Survey 2015-2016 (n 5811) were used to estimate the mean exposure to methylmercury and EPA + DHA in the current and the alternative scenarios considered. Alternative scenarios (alt) were modelled using probabilistic approaches to reflect substitutions from the current consumption in the type of fish/seafood (alt1: excluding predatory fishes; alt2: including only methylmercury low-level fishes) or in the frequency of weekly fish/seafood consumption (alt3 to alt6: 1, 3, 5 or 7 times a week, replacing fish/seafood meals with meat or others). The overall health impact of these scenarios was quantified using disability-adjusted life years (DALY). In the Portuguese population, about 11 450 DALY could be prevented each year if the fish/seafood consumption increased to a daily basis. However, such a scenario would result in 1398 extra DALY considering the consumption by pregnant women and the respective risk on fetal neurodevelopment. Our findings support a recommendation to increase fish/seafood consumption up to 7 times/week. However, for pregnant women and children, special considerations must be proposed to avoid potential risks on fetal neurodevelopment due to methylmercury exposure.

Levels of metals and elements in tissues of fish species in the Kızılırmak River (Turkey) and assessment of health risks and nutritional benefits

Although the Kızılırmak River, the longest river in Turkey, is home to many fish species, there are a few studies reporting metal levels in fish in the river. The contents of 17 metals and elements (MEs) in various tissues of three fish species and surface water from the river were investigated. Significant differences in the ME levels among tissues were recorded, and the highest levels of most MEs were recorded in the gills and liver. The results revealed that correlations between MEs in tissues and fish size were not clear and consistent. Among the MEs, P (6058-109489) and Zn (933-47556) had the highest bioconcentration factor values. The levels of As and Cd in the river water exceeded water quality criteria. Health risk assessment methods (Target Hazard Quotient, Estimated Daily Intake and Lifetime Carcinogenic Risk) indicated that consumption of the studied fish species is safe. It was estimated that a weekly consumption of 490 g of C. gibelio, or 350 g of C. carpio or 280 g of T. tinca would not cause any health risks. Furthermore, it was found that fish species would provide significant benefits in terms of intake of nutrients such as P, K, Ca, Mg, Cu, Zn, Fe and Mn. These findings revealed that nutritional benefits from consumption of fish species outweigh the health risks posed by metals in fish.

Species, tissue and gender-related metal and element accumulation in fish species in a large reservoir (Turkey) and health risks and nutritional benefits for consumers

Concentrations of 18 metals and elements (MEs) in the gills, skin, muscle and liver of Carasobarbus luteus and Cyprinus carpio from the Atatürk Reservoir in Turkey were investigated. The results revealed that variations in the ME contents between fish species can be attributed to different diets. The highest contents of most MEs were recorded in the gills. Gender had no significant effect on the contents of most MEs in the tissues of fish species investigated. The relations between MEs in tissues and fish size were not clear and consistent. Health risk assessment methods indicated that consumption of the studied fish species is safe. It was estimated that daily consumption of 140 g of C. carpio or 170 g of C. luteus would not be expected to cause any health risks. Furthermore, it was found that fish species would provide significant benefits in terms of intake of essential MEs.

Pesticide residues in Rita rita and Cyprinus carpio from river Ganga, India, and assessment of human health risk

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Accumulation of pesticide residues in fish due to continuous use in agricultural areas along river Ganga basin.

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Residues concentrate in the humans through consumption of food from the river.

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Health impacts like non-carcinogenic (THQ) and carcinogenic (R) risks are never negligible by these residues.

Present study was carried out to determine the concentration and bioaccumulation of pesticide residues in two commonly edible fishes: bagrid fish, Rita rita and common carp, Cyprinus carpio collected from river Ganga at Narora, India. The human health risk via consumption of these fishes was also assessed. The n-hexane extract of the muscle tissues was characterized by gas chromatography coupled to mass spectrometry and quantified by electron capture detector for pesticide residues. Bioaccumulation factor (BAF) in bagrid fish for detected pesticides was found to be higher than those in common carp. Estimated daily intake (EDI) values in our study were insignificantly higher than Average daily intake (ADI) values. Target hazard quotient (THQ) via consumption of selected fishes was found to be lower than the set 1.0, inferring non-carcinogenic risk. With regard to contaminants carcinogenic effects the total risk ratio (R) values of each pesticide was found lower than threshold risk limit except of heptachlor which indicates carcinogenic risk. The results justify pesticide pollution in river Ganga at Narora and thus more attention is required in order to help improve the health status of this ecosystem and reduce contamination of fishes.

Equatorial Atlantic pelagic predators reveal low content of PBDEs in contrast to MeO-BDEs: An analysis of brominated diphenyl ethers in blue shark and yellowfin tuna

Polybrominated diphenyl ethers (PBDEs) and their methoxylated analogues (MeO-BDEs) are widely distributed in the environment. The main concern about the presence of PBDEs and MeO-BDEs in fish is due to their potential endocrine disruption effects in the specimens, and their potential risk to the health of human consumers. Considering these concerns, the goal of this study was to investigate the occurrence of PBDEs and MeO-BDEs in muscle tissues of blue shark (BSH), Prionace glauca, and yellowfin tuna (YFT), Thunnus albacares, caught in the Equatorial Atlantic Ocean (EAO), North-eastern Brazilian waters, and to evaluate the potential risk of human exposure by consumption. Muscle tissues of YFT and BSH were extracted using a Soxhlet apparatus and an Accelerated Solvent Extractor (ASE), respectively. PBDEs and MeO-BDEs were analysed by GC-NCI-MS. Concentrations of PBDEs ranged from not detected (nd) to 10 ng g^-1 lipid weight (lw) in YFT muscle samples, while PBDE levels in BSH muscle samples ranged from <LOQ to 34 ng g^-1 lw. Regarding MeO-BDEs, the concentration ranged from 55 to 578 ng g^-1 lw and from <LOQ to 263 ng g^-1 lw in YFT and BSH muscle samples, respectively. MeO-BDE congeners contribution in both YFT and BSH indicated a predominance of 2'-MeO-BDE-68, which is associated to the sponges or sponge-microbiota metabolites. ∑PBDE were statistically similar between YFT and BSH, as well as observed for ∑MeO-BDE. PBDEs and MeO-BDEs in YFT and BSH represent a low potential risk of human exposure through the consumption of edible tissues. Further studies are necessary for a complete assessment of human safety and species conservation.

Approaches for Health Effect Characterization in Risk-Benefit Assessment of Foods: A Comparative Case Study

One of the challenges in quantitative risk-benefit assessment (RBA) of foods is the choice of approach for health effect characterization to estimate the health impact of dietary changes. The purpose of health effect characterization is to describe an association between intake of a food or food component and a health effect in terms of a dose-response relationship. We assessed the impact of the choice of approach for health effect characterization in RBA in two case studies based on substitution of (i) white rice by brown rice and (ii) unprocessed red meat by vegetables. We explored this by comparing the dose-response relations linking a health effect with (i) a food component present in the food, (ii) a food based on non-specified substitution analyses, and (iii) a food based on specified substitution analyses. We found that the choice of approach for health effect characterization in RBA may largely impact the results of the health impact estimates. Conducting the calculations only for a food component may neglect potential effects of the food matrix and of the whole food on the diet-disease association. Furthermore, calculations based on associations for non-specified substitutions include underlying food substitutions without specifying these. Data on relevant specified substitutions, which could reduce this type of bias, are unfortunately rarely available. Assumptions and limitations of the health effect characterization approaches taken in RBA should be documented and discussed, and scenario analysis is encouraged when multiple options are available.

Human health risk-benefit assessment of fish and other seafood: a scoping review

Fish and other seafood are important sources of nutrients, but they are also sources of chemical contaminants that may cause adverse health effects. This article aimed to identify existing risk-benefit assessments (RBA) of fish, shellfish, and other seafood, compare methodologies, discuss differences and commonalities in findings, and identify limitations and ways forward for future studies. We conducted a scoping review of the scientific literature of studies in all languages published from 2000 through April 2019. We identified 106 RBA of fish and other seafood across Europe, Asia, North America, Africa, and at the global level. Studies were heterogeneous in terms of types of fish and other seafood considered, beneficial and adverse compounds assessed, and overall methodology. Collected data showed that a diet consisting of a variety of lean and fatty fish and other seafood is recommended for the overall population and that women of childbearing age and children should limit the consumption of fish and other seafood types that have a high likelihood of contamination. Our review emphasizes the need for evidence-based, up-to-date, and harmonized approaches in RBA in general.

The burden of disease of three food-associated heavy metals in clusters in the Danish population - Towards targeted public health strategies

Lifestyle and sociodemographics are likely to influence dietary patterns, and, as a result, human exposure to chemical contaminants in foods and their associated health impact. We aimed to characterize subgroups of the Danish population based on diet and sociodemographic indicators, and identify those bearing a higher disease burden due to exposure to methylmercury (MeHg), cadmium (Cd) and inorganic arsenic (i-As). We collected dietary, lifestyle, and sociodemographic data on the occurrence of chemical contaminants in foods from Danish surveys. We grouped participants according to similarities in diet, lifestyle, and sociodemographics using Self-Organizing Maps (SOM), and estimated disease burden in disability-adjusted life years (DALY). SOM clustering resulted in 12 population groups with distinct characteristics. Exposure to contaminants varied between clusters and was largely driven by intake of fish, seafood and cereal products. Five clusters had an estimated annual burden >20 DALY/100,000. The cluster with the highest burden had a high proportion of women of childbearing age, with most of the burden attributed to MeHg. Individuals belonging to the top three clusters had higher education and physical activity, were mainly non-smokers and lived in urban areas. Our findings may facilitate the development of preventive strategies targeted to the most affected subgroups.

Public health risk-benefit assessment of red meat in France: Current consumption and alternative scenarios

Consumption of red meat has been associated with the risks of colorectal cancer (CRC), cardiovascular disease (CVD), foodborne-pathogen related diseases and with the potential benefit obtained by reduction of iron deficiency anemia (IDA). Based on probabilistic models, current risks and benefit for the French population were aggregated into a single metric, the disability adjusted life years (DALY). In France, per 100,000 people, current red meat consumption was responsible for a mean of 19 DALYs due to CRC, 21 DALYs to CVD and 7 DALYs to foodborne diseases. Current consumption of iron throughout the diet led to a mean of 15 DALYs due to IDA. To mitigate the risks, scenarios were built per sub-population of age and gender. Among adult and elderly population, the big meat eaters would benefit to adhere to the current recommendation (less than 500 g/w): the risks of CRC and CVD would decrease. Regarding IDA (scenario built with fixed ground beef amount), for young population, a consumption of 375g/w would be sufficient to eliminate the burden while for 25-44 years-old females, 455g/w would reduce IDA, but not entirely. This study highlighted the importance of assessing health risk-benefit per sub-populations and the necessity of communicating the results accordingly.

Risk-benefit in food safety and nutrition - Outcome of the 2019 Parma Summer School

Risk-benefit assessment is the comparison of the risk of a situation to its related benefits, i.e. a comparison of scenarios estimating the overall health impact. The risk-benefit analysis paradigm mirrors the classical risk analysis one: risk-benefit assessment goes hand-in-hand with risk-benefit management and risk-benefit communication. The various health effects associated with food consumption, together with the increasing demand for advice on healthy and safe diets, have led to the development of different research disciplines in food safety and nutrition. In this sense, there is a clear need for a holistic approach, including and comparing all of the relevant health risks and benefits. The risk-benefit assessment of foods is a valuable approach to estimate the overall impact of food on health. It aims to assess together the negative and positive health effects associated with food intake by integrating chemical and microbiological risk assessment with risk and benefit assessment in food safety and nutrition. The 2019 Parma Summer School on risk-benefit in food safety and nutrition had the objective was to provide an opportunity to learn from experts in the field of risk-benefit approach in food safety and nutrition, including theory, case studies, and communication of risk-benefit assessments plus identify challenges for the future. It was evident that whereas tools and approaches have been developed, more and more case studies have been performed which can form an inherent validation of the risk-benefit approach. Executed risk-benefit assessment case studies apply the steps and characteristics developed: a problem formulation (with at least 2 scenarios), a tiered approach until a decision can be made, one common currency to describe both beneficial and adverse effects (DALYs in most instances). It was concluded that risk-benefit assessment in food safety and nutrition is gaining more and more momentum, while also many challenges remain for the future. Risk-benefit is on the verge of really enrolling into the risk assessment and risk analysis paradigm. The interaction between risk-benefit assessors and risk-benefit managers is pivotal in this, as is the interaction with risk-benefit communicators.

Effects of seafood consumption on mercury exposure in Norwegian pregnant women: A randomized controlled trial

BACKGROUND

Seafood provides nutrients that are important for optimal development of the unborn child. However, seafood is also a source of contaminants including mercury (Hg) and methylmercury (MeHg) that may have adverse effects on neurodevelopment of the fetus. Humans are predominantly exposed to MeHg through seafood consumption, however, levels of MeHg vary considerably between species.

OBJECTIVES

Investigate, in a randomized controlled trial (RCT) during pregnancy, if an increased intake of Atlantic cod (Gadus morhua), a fish species with relatively low levels of MeHg contamination, influences total hair Hg (THHg) concentrations in humans.

METHODS

Pregnant women (n = 137) were enrolled in the RCT "Mommy's Food" (2016-2017), which was designed to increase iodine status. Participants were randomly assigned to intervention (400 g of cod fillets per week) or control (continued habitual diet) groups for 16 weeks (gestational week 20-36). THHg concentrations were measured at baseline and post-intervention using thermal decomposition, amalgamation, and atomic absorption spectrophotometry (US EPA method 7473). The trial is registered in ClinicalTrials.gov, NCT02610959.

RESULTS

Post-intervention, the intervention group had median (inter-quartile range) THHg concentrations of 554 (392-805) µg/kg, and the control group 485 (341-740) µg/kg (p = 0.186). When adjusting for baseline THHg concentrations, there was a significant difference between the groups in those participants with baseline THHg concentrations below 534 µg/kg. Post-intervention, 8% of the study population exceeded the US EPA reference dose in hair (1,000 µg/kg) (intervention group: n = 6, control group: n = 4).

CONCLUSION

THHg concentrations were generally low in both study groups of pregnant women, despite the relatively high seafood intake. While the intervention with 400 g of cod per week slightly increased THHg concentrations, it did not lead to an increase in number of subjects exceeding the US EPA reference dose; a dose level at which no adverse effects are expected to occur over a period of lifetime exposure.

Risk-Benefit Assessment of Foods

Food is an elementary requirement for human life, providing nutrients and essential energy needed for optimal health. But at the same time, food can also be a vehicle of hazardous substances or pathogens that could affect human health negatively. Risk‐benefit assessment (RBA) of foods, a relatively new methodology for decision support, integrates nutrition, toxicology, microbiology, chemistry and human epidemiology for a comprehensive health impact assessment. By integrating health risks and benefits related to food consumption, RBA facilitates science‐based decision‐making in food‐related areas and the development of policies and consumer advice. The present work programme aimed to allow the fellow to become acquainted with the process of RBA and the associated tools needed to assess quantitatively the risks and the benefits through three main activities (i) to learn the different methodologies used for RBA; (ii) to apply these methodologies to a specific case‐study – RBA of raw milk consumption; and (iii) to participate in the main activities of the Risk‐Benefit research group at DTU Food regarding risk‐benefit issues. For the RBA of raw milk consumption, microbiological pathogens (Listeria monocytogenes, Salmonella spp., Campylobacter jejuni and Shiga toxin‐producing Escherichia coli), probiotic bacteria and nutritional components (vitamins B2 and A) were considered, as well as the potential impact of raw milk consumption in the reduction of the allergies’ prevalence. Two major approaches were applied: the bottom‐up (estimating the disease incidence due to the exposure) and the top‐down (using epidemiological and incidence data to the estimate the number of cases attributable to a certain exposure). Through all the training and hands‐on activities performed, the present work programme enabled the fellow to extend the knowledge on the quantitative RBA, specifically in the context of raw milk consumption. EU‐FORA programme also provided an exceptional opportunity of networking and establishment of future research lines of collaboration.

Nutritional Value and Contaminant Risk Assessment of Some Commercially Important Fishes and Crawfish of Lake Trasimeno, Italy

The aim of our study was to describe the balance between health benefits and risks associated with the consumption of crawfish and nine fish species from lake Trasimeno. We thus determined both fatty acid profiles (particularly, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids) and chemical pollutants (some polychlorinated biphenyls, pesticides, and heavy metals) in fish muscle tissues. The contents of all fatty acids varied significantly among species. Sand smelt, carp, and tench, which have a high fat content, contained considerable amounts of EPA and DHA; lean fish, like perch, pike, and largemouth bass, which have relatively high percentages of the predominant n-3 fatty acids EPA and DHA, showed lower amounts of these fatty acids because of their low lipid contents. Some species contributed strongly to the Dietary Reference Intake (RDI) of EPA and DHA. The contribution of lean fish to the RDI of EPA and DHA was more limited. The concentrations of all contaminants in fish muscle tissues were lower than the regulatory limits, demonstrating the safety of the environmental conditions of the lake. The contribution to health-based reference values and benefit–risk quotients indicated that the health benefits of consumption of fish from lake Trasimeno outweigh the potential risks.

Estimation of the burden of disease attributable to red meat consumption in France: Influence on colorectal cancer and cardiovascular diseases

The consumption of red meat has been associated with colorectal cancer (CRC) and cardiovascular disease (CVD) worldwide. The objective of this study was to assess quantitatively the burden of disease of CRC and CVD due to the consumption of red meat in France. A probabilistic risk assessment model quantifying the risk, deaths and disability adjusted life years (DALY) of both outcomes was built. In the model, uncertainty and variability were propagated separately. The model used data on current CRC and CVD incidence and red meat consumption in France, as well as dose-response from epidemiological studies. Results were given by age class and gender. A total of 19 [95% CI = 8-33] DALY per 100,000 people per year for CRC associated with red meat consumption was estimated. For CVD, 21 [95% CI = 12-32] DALY per 100,000 people per year was estimated. The uncertainty was mainly due to the dose-response, as revealed by a sensitivity analysis. A scenario analysis, performed on red meat intake, highlighted that consumption of less than 65 g per day could limit the risk of CRC and CVD in the most affected sub-populations.

A probabilistic approach for risk-benefit assessment of food substitutions: A case study on substituting meat by fish

Accounting for substitution of foods is inevitable when evaluating health impact of dietary changes. But substitution behavior and the associated health impact may vary between individuals. We therefore propose the use of probabilistic methods to model substitution and assess health impact distributions in risk-benefit assessment (RBA) of foods. We investigated the health impact of substituting red and processed meat with fish in the Danish adult population and the variability in health impact. We applied probabilistic approaches in modeling the substitution to reflect variability between individual substitution behaviors. Furthermore, when multiple intake scenarios are compared, we propose a method for adjusting intake differences for individual day-to-day variability. We estimated that 134 (95% UI: 102; 169) Disability-Adjusted Life Years/100,000 were averted per year by the substitution. The health impact varied considerably by age and sex, with the largest health benefit of the substitution observed for young women in the child-bearing age and for the older generation, mainly men. This study provides further insight in how the health impact of substituting meat by fish varies between individuals and suggests a framework to be applied in RBAs of other food substitutions. Our results are relevant for policy makers in defining targeted public health strategies.

Risk Benefit Assessment of foods: Key findings from an international workshop

Whilst risk management measures, including food policy, are developed for the protection of public health and the environment, they may also lead to a reduction in health benefits. Policy decisions require then consideration of these necessary trade-offs, which leads to an increasing need to apply formal risk-benefit assessment (RBA) of foods. In this context, the European Food Safety Authority sponsored a Risk-Benefit Assessment Workshop on "past, current and future developments within the risk-benefit assessment of foods (RBA)" held in May 2017. The overall aims of the RBA Workshop were to discuss existing methods, challenges and needs within RBA, and to draft a roadmap for future development of RBA. The specific objectives were to i) identify RBA activities in Europe and globally; ii) discuss how to further develop and optimize RBA methodology; iii) identify challenges and opportunities within RBA; and iv) increase collaboration internationally. The two-day workshop gathered 28 participants from 16 institutions in 11 countries. It included technical presentations of RBA methods and case studies, and two break-out sessions for group discussions. All participants agreed that RBA has substantial potential to inform risk-management decisions in the areas of food safety, nutrition and public health. Several activities to optimize further developments within RBA were suggested. This paper provides a summary of workshop presentations, a discussion of challenges that limit progress in this area, and suggestions of next steps for this promising approach supporting a science-based decision process in the area of risk-benefit management of foods.

Investigating the risk-benefit balance of substituting red and processed meat with fish in a Danish diet

Danish dietary guidelines recommend the Danish population to increase the consumption of fish while decreasing the consumption of red and processed meat to prevent nutrition-related diseases. However, the presence of contaminants in these foods may affect the overall risk-benefit balance of such substitution. We performed a quantitative risk-benefit assessment on substituting red and processed meat with fish in a Danish diet. We modeled the substitution among Danish adults based on data from a Danish dietary survey and compared four alternative scenarios based on varying chemical and nutrient exposures to the current consumption. We quantified the overall health impact of the substitutions in terms of Disability-Adjusted Life Years (DALYs). Approximately 150 DALYs/100,000 individuals could be averted each year if Danish adults consumed 350 g of fish/week (fatty or mix of fatty and lean) while decreasing the consumption of red and processed meat. A lower beneficial impact was observed when consumption of fish was restricted to lean fish (80 DALYs/100,000 averted), and a marked health loss (180 DALYs/100,000) was estimated when consumption was restricted to tuna. Our results show an overall beneficial effect of the substitution if the consumption of large predatory fish is low and at least half is fatty fish.

Ensuring Food Integrity by Metrology and FAIR Data Principles

Food integrity is a general term for sound, nutritive, healthy, tasty, safe, authentic, traceable, as well as ethically, safely, environment-friendly, and sustainably produced foods. In order to verify these properties, analytical methods with a higher degree of accuracy, sensitivity, standardization and harmonization and a harmonized system for their application in analytical laboratories are required. In this view, metrology offers the opportunity to achieve these goals. In this perspective article the current global challenges in food analysis and the principles of metrology to fill these gaps are presented. Therefore, the pan-European project METROFOOD-RI within the framework of the European Strategy Forum on Research Infrastructures (ESFRI) was developed to establish a strategy to allow reliable and comparable analytical measurements in foods along the whole process line starting from primary producers until consumers and to make all data findable, accessible, interoperable, and re-usable according to the FAIR data principles. The initiative currently consists of 48 partners from 18 European Countries and concluded its "Early Phase" as research infrastructure by organizing its future structure and presenting a proof of concept by preparing, distributing and comprehensively analyzing three candidate Reference Materials (rice grain, rice flour, and oyster tissue) and establishing a system how to compile, process, and store the generated data and how to exchange, compare them and make them accessible in data bases.

Use of Mathematical Optimization Models to Derive Healthy and Safe Fish Intake

Background

Recommended fish intake differs substantially from observed fish intake. In Denmark, ∼15% of the population consumes the state-recommended fish intake. How much fish individuals eat varies greatly, and this variation cannot be captured by considering the fish intake of the average population.

Objective

We developed a method intended to provide realistic and achievable personalized dietary recommendations based on an individual's body weight and current fish intake. The objective of the study was to propose specific fish intake levels for individuals that meet the recommendations for eicosapentaenoic acid, docosahexaenoic acid, and vitamin D without violating the permitted intake recommendations for methyl mercury, dioxins, and polychlorinated biphenyls.

Methods

Two mathematical optimization models were developed that apply quadratic programming to model personalized recommended fish intake, fulfilling criteria on nutrients and contaminants, while simultaneously deviating as little as possible from observed individual intake. A recommended intake for 8 fish species was generated for each individual in a group of 3016 Danes (1552 women and 1464 men, aged 18-75 y), whose fish intakes and body weights were known from a national dietary survey.

Results

Individual, personal dietary recommendations were successfully modeled. Modeled fish intake levels were compared to observed fish intakes. For women, the average proposed increase in fish intake was 14 g/wk for lean fish and 63 g/wk for fatty fish; and for men these numbers were 12 and 55 g/wk, respectively.

Conclusions

Using fish intake as an example, we show how quadratic programming models may be used to advise individual consumers how to optimize their diet, taking both benefits and risks into account. This approach has the potential to increase compliance with dietary guidelines by targeting the individual consumers and minimizing the need for large and ultimately unrealistic behavior changes.

Disease burden of methylmercury in the German birth cohort 2014

This study aimed to estimate the disease burden of methylmercury for children born in Germany in the year 2014. Humans are mainly exposed to methylmercury when they eat fish or seafood. Prenatal methylmercury exposure is associated with IQ loss. To quantify this disease burden, we used Monte Carlo simulation to estimate the incidence of mild and severe mental retardation in children born to mothers who consume fish based on empirical data. Subsequently, we calculated the disease burden with the disability-adjusted life years (DALY)-method. DALYs combine mortality and morbidity in one measure and quantify the gap between an ideal situation, where the entire population experiences the standard life expectancy without disease and disability, and the actual situation. Thus, one DALY corresponds to the loss of one year of life in good health. The methylmercury-induced burden of disease for the German birth cohort 2014 was an average of 14,186 DALY (95% CI 12,915-15,440 DALY). A large majority of the DALYs was attributed to morbidity as compared to mortality. Of the total disease burden, 98% were attributed to mild mental retardation, which only leads to morbidity. The remaining disease burden was a result of severe mental retardation with equal proportions of premature death and morbidity.

Development and Application of a Probabilistic Risk-Benefit Assessment Model for Infant Feeding Integrating Microbiological, Nutritional, and Chemical Components

A probabilistic and interdisciplinary risk-benefit assessment (RBA) model integrating microbiological, nutritional, and chemical components was developed for infant milk, with the objective of predicting the health impact of different scenarios of consumption. Infant feeding is a particular concern of interest in RBA as breast milk and powder infant formula have both been associated with risks and benefits related to chemicals, bacteria, and nutrients, hence the model considers these three facets. Cronobacter sakazakii, dioxin-like polychlorinated biphenyls (dl-PCB), and docosahexaenoic acid (DHA) were three risk/benefit factors selected as key issues in microbiology, chemistry, and nutrition, respectively. The present model was probabilistic with variability and uncertainty separated using a second-order Monte Carlo simulation process. In this study, advantages and limitations of undertaking probabilistic and interdisciplinary RBA are discussed. In particular, the probabilistic technique was found to be powerful in dealing with missing data and to translate assumptions into quantitative inputs while taking uncertainty into account. In addition, separation of variability and uncertainty strengthened the interpretation of the model outputs by enabling better consideration and distinction of natural heterogeneity from lack of knowledge. Interdisciplinary RBA is necessary to give more structured conclusions and avoid contradictory messages to policymakers and also to consumers, leading to more decisive food recommendations. This assessment provides a conceptual development of the RBA methodology and is a robust basis on which to build upon.

Prenatal low-level mercury exposure and infant neurodevelopment at 12 months in rural northern China

Although MeHg is a confirmed neurotoxin at sufficiently high dosages, the effect of prenatal low-level Hg exposure on infant neurodevelopment is still unknown. Four hundred ten mother-infant pairs were recruited in rural northern China from September 2010 to September 2012. We investigated maternal diet during pregnancy, collected maternal and umbilical blood samples, and tested infant neurodevelopment using Gesell developmental schedules (GDS) at the age of 1 year old. The geometric means (GM) of Hg exposure in maternal and umbilical blood were 0.72 and 1.2 μg/L, respectively. Positive associations between Hg levels and the frequency of total fish consumption were found (Spearman's correlation, r = 0.09 for maternal Hg, r = 0.14 for umbilical Hg, p < 0.01). After adjusting for confounding factors, we found a log-unit increase in umbilical blood Hg levels was associated with a 4.22-point (95 % confidence interval (95 %CI) 0.77 to 7.67) increase in the adaptive domain and a 4.06-point (95 %CI 0.51 to 7.62) increase in the social domain. No significant association has been found between other domains and Hg levels in our study. In further analysis, we noticed the positive correlation between the developmental quotient (DQ) scores of the adaptive domain and frequencies of total fish consumption (p = 0.04). Our results failed to indicate the adverse effects between prenatal Hg exposure and infant neurodevelopment. However, given the low-level Hg exposure and its predominant source, the potential positive associations in our study may be attributed to the beneficial nutrients of fish consumption.

Comparison of the nutritional and toxicological reference values of trace elements in edible marine fish species consumed by the population in Rio De Janeiro State, Brazil

The present study estimated the human daily and weekly intake of inorganic elements due to consumption of fish in Rio de Janeiro state and the associated potential health risks posed by some toxic elements. All samples analyzed had values of Cd and Pb below the Maximum Tolerable Limits of 3.0 mg kg⁻¹ for Pb and 1.0 mg kg⁻¹ for Cd; only Mugil cephalus, Cynoscion leiarchus and Caranx crysos had As concentrations below 1 mg kg⁻¹, maximum limit established by Brazilian legislation. The higher values of Cd and Pb correspond to 0.22% of PTWI and the higher value of As corresponds to 8.6% of PTWI. None of the studied species showed values higher than PTWI. The higher values of Cu EDI found in Pomatomus numida correspond to 33.3% of RDA; Fe in Salmo salar and Genypterus brasiliensis corresponds to 4.3% of EDI; Mn in Sardinella brasiliensis corresponds to 7.4% of EDI; Zn in S. salar corresponds to 13.2% of EDI and Se in S. salar corresponds to 20.6% of EDI. Some species can be a good source of inorganic elements. For risk assessment, it is important to assess specific eating habits of each region to avoid underestimating the data.

Perceptions and experiences of environmental health risks among new mothers: a qualitative study in Ontario, Canada

There is a growing awareness and concern in contemporary societies about potential health impacts of environmental contaminants on children. Mothers are traditionally more involved than other family members in managing family health and household decisions and thus targeted by public health campaigns to minimise risks. However little is known about how new mothers perceive and experience environmental health risks to their children. In 2010, we undertook a parallel case study using qualitative, in-depth interviews with new mothers and focus groups with public health key informants in two Public Health Units in Ontario Province, Canada. We found that the concern about environmental hazards among participants ranged from having no concerns to actively incorporating prevention into daily life. Overall, there was a common perception among participants that many risks, particularly in the indoor environment, were controllable and therefore of little concern. But environmental risks that originate outside the home were viewed as less controllable and more threatening. In response to such threats, mothers invoked coping strategies such as relying on the capacity of children's bodies to adapt. Regardless of the strategies adopted, actions (or inactions) were contingent upon active information seeking. We also found an optimistic bias in which new mothers reported that other children were at greater risk despite similar environmental circumstances. The findings suggest that risk communication experts must attend to the social and environmental contexts of risk and coping when designing strategies around risk reducing behaviours.

Mercury as a global pollutant: sources, pathways, and effects

Mercury (Hg) is a global pollutant that affects human and ecosystem health. We synthesize understanding of sources, atmosphere-land-ocean Hg dynamics and health effects, and consider the implications of Hg-control policies. Primary anthropogenic Hg emissions greatly exceed natural geogenic sources, resulting in increases in Hg reservoirs and subsequent secondary Hg emissions that facilitate its global distribution. The ultimate fate of emitted Hg is primarily recalcitrant soil pools and deep ocean waters and sediments. Transfers of Hg emissions to largely unavailable reservoirs occur over the time scale of centuries, and are primarily mediated through atmospheric exchanges of wet/dry deposition and evasion from vegetation, soil organic matter and ocean surfaces. A key link between inorganic Hg inputs and exposure of humans and wildlife is the net production of methylmercury, which occurs mainly in reducing zones in freshwater, terrestrial, and coastal environments, and the subsurface ocean. Elevated human exposure to methylmercury primarily results from consumption of estuarine and marine fish. Developing fetuses are most at risk from this neurotoxin but health effects of highly exposed populations and wildlife are also a concern. Integration of Hg science with national and international policy efforts is needed to target efforts and evaluate efficacy.

Qalibra: a general model for food risk-benefit assessment that quantifies variability and uncertainty

The EU project BRAFO proposed a framework for risk-benefit assessment of foods, or changes in diet, that present both potential risks and potential benefits to consumers (Hoekstra et al., 2012a). In higher tiers of the BRAFO framework, risks and benefits are integrated quantitatively to estimate net health impact measured in DALYs or QALYs (disability- or quality-adjusted life years). This paper describes a general model that was developed by a second EU project, Qalibra, to assist users in conducting these assessments. Its flexible design makes it applicable to a wide range of dietary questions involving different nutrients, contaminants and health effects. Account can be taken of variation between consumers in their diets and also other characteristics relevant to the estimation of risk and benefit, such as body weight, gender and age. Uncertainty in any input parameter may be quantified probabilistically, using probability distributions, or deterministically by repeating the assessment with alternative assumptions. Uncertainties that are not quantified should be evaluated qualitatively. Outputs produced by the model are illustrated using results from a simple assessment of fish consumption. More detailed case studies on oily fish and phytosterols are presented in companion papers. The model can be accessed as web-based software at www.qalibra.eu.

Lipid and fatty acid composition, and persistent organic pollutant levels in tissues of migrating Atlantic bluefin tuna (Thunnus thynnus, L.) broodstock

Lipid class, fatty acid and POP levels were measured in migrating Atlantic bluefin tuna (ABT) tissues caught off the Barbate coast, Spain. Tissue lipids were largely characterized by triacylglycerol, reflecting large energy reserves accumulated prior to reproductive migration. Fatty acid compositions of muscle, liver and adipose exhibited similar profiles, whereas gonads showed a higher affinity for docosahexaenoic acid. Tissue POP concentrations correlated positively with percentage triacylglycerol and negatively with polar lipids. Highest POP concentrations were in adipose and lowest in gonads, reflecting lipid content. DL-PCBs contributed most to total PCDD/F + DL-PCB levels, with mono-ortho concentrations higher in tissues, whereas non-ortho PCBs contributed greater WHO-TEQs due to differences in TEFs. PBDE47 was the most prominent BDE congener in tissues, probably through biotransformation of BDE99 and other higher brominated congeners. The perceived POP risk from ABT consumption should be balanced by the well-established beneficial effects on human health of omega-3 fatty acids.